Long-term creatine supplementation does not significantly affect clinical health markers in athletes
Kreider, Melton, Rasmussen, Greenwood, Lancaster, Cantler, Milnor & Almada (2003) · Molecular and Cellular Biochemistry
Topics: Safety & Kidney
- Study type: Cohort study
- Population: Collegiate athletes
- Dose: Up to 15.75 g/day (varied)
- Duration: Up to 21 months
- Published: 2003
What the study found
Following athletes taking creatine for up to 21 months, researchers found no clinically significant effects on comprehensive markers of health — including kidney, liver, and metabolic panels — reinforcing the long-term safety profile.
Key findings
- No clinically meaningful changes across 54 blood and urine health markers.
- Liver and kidney function remained normal over the study period.
- Adds long-duration, real-athlete data to the safety literature.
The practical takeaway
Extended, real-world use in athletes shows no harm to standard health markers.